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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 16 |
| 5 | 38 |
| 6 | 95 |
| 7 | 250 |
| 8 | 689 |
| 9 | 1972 |
| 10 | 5809 |
| 11 | 17484 |
| 12 | 53497 |
| 13 | 165845 |
| 14 | 519681 |
| 15 | 1643112 |
| 16 | 5234728 |
| 17 | 16785774 |
| 18 | 54128870 |
| 19 | 175409177 |
| 20 | 570906174 |
| 21 | 1865364061 |
| 22 | 6116175260 |
| 23 | 20117351296 |
| 24 | 66361157675 |
| 25 | 219484396545 |
| 26 | 727692105683 |
| 27 | 2418048043653 |
| 28 | 8051628061939 |
| 29 | 26862111773042 |
| 30 | 89779489887570 |
| 31 | 300568375668272 |
| 32 | 1007841476081366 |
[0,1,3,7,16,38,95,250,689,1972,5809,17484,53497, 165845,519681,1643112,5234728,16785774,54128870, 175409177,570906174,1865364061,6116175260, 20117351296,66361157675,219484396545,727692105683, 2418048043653,8051628061939,26862111773042, 89779489887570,300568375668272,1007841476081366] |